THE ASSOCIATION IN CLASS FESTUCO-BROMETEA Br.-Bl. et R. Tx. IN Br.-Bl FROM THE COVURLUI PLATEAU

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1 BIOLOGY THE ASSOCIATION IN CLASS FESTUCO-BROMETEA Br.-Bl. et R. Tx. IN Br.-Bl FROM THE COVURLUI PLATEAU DIDIA POPA 1, T. CHIFU 2 and IRINA IRIMIA 2 The authors describe 6 well spread associations from the Covurlui Plateau and Plain. Floristic and phytocoenologic composition, bioforms spectrum, phytogeographic elements and ecological indices are analysed for those associations. Also economical value is discussed. Key words: phytocoenosis, bioforms, geoelements. INTRODUCTION Pastures from the Covurlui Plateau and Plain are well spread, most of the areas being covered by Festuco-Brometea. Vegetal associations presented in this paper were identified in various location in Moldavia [3, 6] and the entire country (Romania) [8], and also in many locations we have investigated [1, 8 12]. Therefore, our research tries to complete previous studies with new data form locations never mentioned before. RESULTS AND DISCUSSIONS Identified vegetal associations are part of the following coenosystem [2, 3]: Festuco Brometea Br.-Bl. et R. Tx. in Br.-Bl Festucetalia valesiacae Br.-Bl. et R. Tx. ex Br.-Bl Festucion valesiacae Klika 1931 Jurineo arachnoideae Euphorbinenion nicaeensis Dobrescu et. Kovács 1971 corr. Sârbu, Coldea et Chifu 1993 Ass. Taraxaco serotinae Festucetum valesiacae (Burduja et al. 1956) Sârbu, Coldea et Chifu 1979 Ass. Taraxaco serotinae Bothriochloetum ischaemi (Burduja et al. 1956) Sârbu, Coldea, et Chifu 1979 Ass. Artemisio austriacae Poëtum bulbosae I. Pop 1970 Ass. Cynodonti Poëtum angustifoliae (Rapaics 1927) Soó 1957 Ass. Bromo squarrosi Xeranthemetum annui Coroi 2001

2 58 Didia Popa et al. 2 Festucetalia vaginatae Soó 1957 Bromion tectorum Soó 1957 Ass. Brometum tectorum Bojko 1934 We have to mention that bioforms and phytogeographic elements information was extracted from Ciocârlan, 2000 [4], ecological indices from Sanda et al [5], and information about protected species, from Oltean et al [7]. Ass. Taraxaco serotinae Festucetum valesiacae (Burduja et al. 1956) Sârbu, Coldea et Chifu 1979 (Syn.: Festucetum valesiacae Burduja et al. 1956) Chorology. The association is more prevalent in wide pastures and forest clearings. Relevant surveys are from Suceveni, Zărneşti, Crăieşti, Jorăşti, Pupezeni, Rădeşti, Roşcani, Vlădeşti and Bursucani. Stationary conditions. The phytocoenoses established by Festuca valesiaca are located on plateaus with a low or moderate inclination, rarely on higher slopes, with mostly north expositions with quasi degraded chernosem soil (Sârbu 1984). The floristic and phytocoenological composition (Table 1). The association has an average floristic composition, 125 species, with an average of 47 species/survey. Along with characteristically specie Taraxacum serotinum and the main specie Festuca valesiaca, coexist a large number of other species (75%) characteristic for the class Festuco-Brometea. One can remark high constancy species (IV and V), like: Eryngium campestre, Artemisia austriaca, Astragalus onobrychis, Salvia pratensis, Filipendula vulgaris, Medicago falcata, Medicago minima, Thymus pannonicus, Achillea setacea, Salvia nemorosa, Euphorbia cyparissias, Potentilla argentea, Plantago lanceolata, Hieracium pilosella etc. Low participating in the floristic composition (6 10%) are the species from the class Molinio Arrhenatheretea, Artemisietea and Stellarietea mediae, having an average to low constancy (III I). Table 1 Ass. Taraxaco serotinae Festucetum valesiacae (Burduja et al., 1956) Sârbu, Coldea et Chifu 1979 No. of survey Altitude (m.s.m.) Exposition NE NV SE SV NV NE SE SE SV NE Slope (degrees) K Coverage of the vegetation (%) Surface (sq.m.) Number of species Caract. of ass. Taraxacum serotinum II

3 3 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 59 Jurineo-Euphorbinenion Ajuga laxmannii II Carduus hamulosus + I Centaurea orientalis + I Chamaecytisus austriacus II Cleistogenes bulgarica II Dianthus membranaceus III Echium maculatum + + I Eryngium campestre V Euphorbia glareosa V Galium humifusum II G. octonarium + + I Iris pumila + I Jurinea arachnoidea + + I Linum hirsutum + + I Salvia austriaca II Stachys germanica III Festucion valesiacae Ajuga chamaepytis II Allium rotundum + I Artemisia austriaca V Asperula cynanchica + + I Aster linosyris + I Astragalus onobrychis IV Chondrilla juncea II Dichanthium ischaemum V Elymus hispidus + I Falcaria vulgaris + + I Filipendula vulgaris IV Fragaria viridis + + I Koeleria macrantha V Linaria genistifolia II Medicago falcata V M. minima IV Potentilla recta + I Salvia pratensis + + I Sanguisorba minor II Senecio erucifolius + + I Stachys recta + I Stipa capillata II Teucrium polium ssp. capitatum + + I Festucetalia valesiacae Achillea collina + + I

4 60 Didia Popa et al. 4 A. setacea V Adonis vernalis + + I Campanula sibirica II Centaurea biebersteinii III Cerastium semidecandrum + I Ceratocarpus arenarius + + I Echium vulgare III Euphorbia cyparissias IV Festuca valesiaca V Hieracium bauhinii III Hypericum perforatum III Galium verum III Linum austriacum III Melica ciliata II Ornithogalum orthophyllum ssp. + I kochii Phleum phleoides II Potentilla pedata + + I Salvia nemorosa IV Sideritis montana + I Silene otites + + I Stachys recta + + I Teucrium chamaedrys III Thymus pannonicus V Trifolium campestre II Verbascum lychnitis + I V. speciosum III Veronica orchidea + + I V. prostrata + I Vinca herbacea + + I Festucetalia vaginatae Alyssum desertorum II Anthemis ruthenica II Bromus squarrosus + + I Erysimum diffusum III Helichrysum arenarium + I Plantago argentea + I P. scabra + I Scabiosa argentea + I S. ochroleuca II Festuco Brometea Acinos arvensis + I Asperula tenella II

5 5 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 61 Carex caryophyllea + + I Centaurea diffusa + + I Crepis foetida ssp. rhoeadifolia IV Cynodon dactylon + + I Daucus carota + + I Hieracium pilosella V Plantago lanceolata IV Poa angustifolia V P. bulbosa III Potentilla argentea V Stachys germenica II Veronica austriaca + + I Xeranthemum annuum III Molinio Arrhenatheretea s.l. Bromus commutatus + I Elymus repens II Lolium perenne + I Lotus corniculatus III Medicago lupulina III Odontites vernus ssp. serotinus + I Trifolium repens II Artemisietea et Stellarietea mediae s.l. Berteroa incana III Carduus acanthoides III Convolvulus arvensis II Descurainia sophia II Erigeron acris + + I Erodium cicutarium III Lappula squarrosa II Nepeta nuda + I Nigella arvensis + + I Picris hieracioides + I Scleranthus annuus + + I Vicia tetrasperma + + I Variae syntaxa Agrimonia eupatoria III Arenaria serpyllifolia III Campanula rapunculus + I Coronilla varia + + I Crataegus monogyna + + I Inula hirta + + I Rosa canina + I Rumex acetosella II

6 62 Didia Popa et al. 6 Thlaspi perfoliatum II Trifolium arvense III T. diffusum + + I Turritis glabra + I Place and date of the surveys: 1. Suceveni, ; 2. Zărneşti, ; 3. Crăieşti, ; 4. Jorăşti, ; 5, Pupezeni, ; 6. Rădeşti, ; 7. Roşcani, ; 8. Vlădeşti, ; 9, 10. Bursucani, The bioforms spectrum (Fig. 1) mostly contains hemicryptophytes (47.4%), along with terophytes and hemiterophytes (36.2%). The phytogeographic elements spectrum (Fig. 2) reveal a large number of Eurasiatics (40.5%) and Pontic elements (25.8%). Ph Ch T G H Ht Fig. 1. The bioforms spectrum in the Taraxaco serotinae Festucetum valesiacae ass. Euras Eur. Eur.centr Circ. Cosm. Med(submed) Pont. Fig. 2. The phytogeographic elements spectrum in the Taraxaco serotinae Festucetum valesiacae ass. The ecological indices spectrum (Fig. 3) indicates the predominance of xeromesophile and xerophile species (83.5%), mesophile and moderate-termophile (77.5%), low acid-neutrophilic and euriionic (54.2%). Economical significance. Festuca valesiaca phytocoenosis are exclusively used for depasturage, therefore the vegetation coverage is relatively low (72%). Only 22% of the species represents forage, and high quality plants are only form species: Lolium perenne, Lotus corniculatus, Medicago falcata, Medicago lupulina, Trifolium repens. Around 70% are non- forage species, and 8% are toxic plants as: Adonis vernalis, Euphorbia cyparissias, Euphorbia glareosa, Artemisia austriaca, Carduus acanthoides, Carduus hamulosus, Descurainia sophia, Eryngium campestre and Rumex acetosella. Ass. Taraxaco serotinae Bothriochloetum ischaemi (Burduja et al. 1956) Sârbu, Coldea et Chifu 1999 (Syn.: Bothriochloa ischemum Burduja et al. 1956)

7 7 The ass. in cl. Festuco-Brometea from the Covurlui Plateau % 80% 60% 40% 20% 0% U T R 6,00 5,50 5,00 4,50 4,00 3,50 3,00 2,50 2,00 1,50 1,00 Fig. 3. The ecological indices spectrum of the Taraxaco serotinae Festucetum valesiacae ass. (U = humidity, T = temperature, R = soil reaction). Chorology. Association is spread in the area of Festuca valesiaca phytocoenosis around localities Suceveni, Rogojeni, Cristeşti, Roşcani, Jorăşti, Zărneşti and Ghingheşti. Stationary conditions. The association was identified around the altitude of m, usually on eroded soils, on hills with inclination up to 25 degree and diverse exposure. The floristic and phytocoenological composition (Table 2). The association is relatively poor (87 species), since the main specie Dichantium ischaemum, has an important coverage (70 80%) in almost any surveys, other species being eliminated over time. The same cause explains the reduced number of species with high frequency (IV and V) almost all of them being non-forager, like: Euphorbia glareosa, Eryngium campestre, Sanguisorba minor, Achillea setacea, Festuca valesiaca, Thymus pannonicus, Poa angustifolia, Potentilla argentea, Plantago lanceolata, Xeranthemum annuum, Cichorium intybus, Berteroa incana etc. Around 80% of the species are specific to the class Festuco Brometea, and 35% of them belong to the sub-alliance Jurineo-Euphorbinenion and the alliance Festucion valesiacae. We have to mention a significant kernel of species (17%) formed by the classes Artemisietea and Stellarietea mediae. Table 2 Ass. Taraxaco Bothriochloetum ischaemum (Burduja et al., 1956) Sârbu, Coldea et Chifu 1999 No. of survey Altitude (m.s.m.) Exposition NV V V E NV V SV SV SV E Slope (degrees) Coverage of the vegetation (%) Surface (sq.m.) K

8 64 Didia Popa et al. 8 Number of species Caract. of ass. Taraxacum serotinum IV Jurineo-Euphorbinenion Ajuga laxmannii + + I Carduus hamulosus + + I Cleistogenes bulgarica + + I Dianthus membranaceus II Eryngium campestre V Euphorbia glareosa IV Jurinea arachnoidea II Echium maculatum + + I Galium humifusum III Salvia austriaca + + I Stachys germanica + + I Festucion valesiacae Ajuga chamaepytis + + I Allium rotundum + + I Artemisia austriaca III Astragalus onobrychis III Chondrilla juncea III Dichanthium ischaemum V Koeleria macrantha III Linaria genistifolia + + I Medicago falcata + + I M. minima + + I Potentilla recta II Sanguisorba minor IV Senecio erucifolius + + I Stipa capillata III Teucrium chamaedrys II Festucetalia valesiacae Achillea setacea V Adonis vernalis + I Campanula sibirica + + I Centaurea biebersteinii II Festuca valesiaca V Euphorbia cyparissias III Hieracium bauhinii III Hypericum perforatum II Salvia nemorosa III Sideritis montana + + I Thymus pannonicus V

9 9 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 65 Festucetalia vaginatae Alyssum desertorum II Anthemis ruthenica + + I Bromus squarrosus II B. tectorum + + I Cynanchum acutum + + I Erysimum diffusum II Onobrychis arenaria + + I Plantago scabra + + I Potentilla arenaria II Scabiosa ochroleuca III Festuco Brometea Acinos arvensis + + I Asperula tenella III Carex caryophyllea + + I Centaurea diffusa III Crepis foetida ssp.rhoeadifolia V Cynodon dactylon III Daucus carota III Hieracium pilosella II Plantago lanceolata V Poa angustifolia V Potentilla argentea V Xeranthemum annuum IV Molinio-Arrhenatheretea s.l. Cichorium intybus IV Equisetum arvense II Eryngium planum + + I Lotus corniculatus III Vicia cracca + I Artemisietea et Stellarietea mediae s.l. Anagallis arvensis + I Artemisia absinthium II Berteroa incana IV Carthamus lanatus + I Erodium cicutarium II Lappula squarrosa + + II Melilotus officinalis + + I Nigella arvensis III Reseda lutea + + I Senecio vernalis II Sisymbrium loeselii + + I Verbascum phlomoides II

10 66 Didia Popa et al. 10 Vicia tetrasperma + + I Variae syntaxa Agrimonia eupatoria III Arenaria serpyllifolia II Coronilla varia II Crataegus monogyna + I Filago arvensis III Rosa canina + I Thlaspi perfoliata + I Trifolium arvense II Place and date of the surveys: 1. Suceveni, ; 2. Rogojeni, , 3. Creţesti, ; 4. Roşcani, ; 5. Jorăşti, ; 6 9. Ghingheşti, ; 10. Zărneşti, The bioforms spectrum (Fig. 4) is dominated by hemicryptophytes (48.1%) but also a significant percentage is represented by terophytes (29.8%). The phytogeographic elements spectrum (Fig. 5) is defined by a high percentage of Eurasiatic elements (57.1%) and also a significant percentage of Pontic elements (19.5%). Ph Ch T G H Ht Ht-H Fig. 4. The bioforms spectrum in the Taraxaco Bothriochloetum ischaemi ass. Euras Eur. Eur.centr Circ. Cosm. Med(submed) Pont. Fig. 5. The phyogeographic elements spectrum in the Taraxaco Bothriochloetum ischaemi ass. Most of the species in the ecological indices spectrum (Fig. 6) are xeromesophile (64.9%) and xerophile (23.3%), micro-mesophile (57.1%) and moderate-termophile (32.4%), low acid-neutrophilic(51.9%) and euriionic (25.9%). Economical significance. Pastures of Dichantium ischaemum have law economical value, only 23% of the species representing forage, and the main specie is useful only in early stages. More over, around 12% of the species are toxic like: Euphorbia glareosa, Equisetum arvense, Eryngium campestre, Eryngium planum etc.

11 11 The ass. in cl. Festuco-Brometea from the Covurlui Plateau % 80% 60% 40% 20% 0% U T R 6,00 5,50 5,00 4,50 4,00 3,50 3,00 2,50 2,00 1,50 1,00 Fig. 6. The ecological indices spectrum of the Taraxaco Bothriochloetum ischaemi ass. (U = humidity, T = temperature, R = soil reaction). Ass. Artemisio austriacae Poëtum bulbosae I. Pop 1970 Chorology. Phytocoenoses consisting of Artemisia austriaca and Poa bulbosa are spread in any pastures in the investigated area, creating compact island of various sizes. Also, due intensive depasturage, a secondary association was installed Festuca valesiaca. Relevant surveys were found around localities: Suceveni, Jorăşti, Vlădeşti, Roşcani, Folteşti and Crăieşti. Stationary conditions. Phytocoenoses consisting of Poa bulbosa and Artemisia austriaca grows on arid lands and moderate inclination hills. The floristic and phytocoenological composition (Table 3). Since stationary conditions in the investigated area are not so varied, a poor floristic composition was observed (62 species). The percentage for the main two species varies during the year, Poa bulbosa is developing well in the spring and beginning of the summer, and Artemisia austriaca, during the summer and fall. Pastures decay caused by intensive depasturage, determined the arise inside the association Artemisio austriacae Poëtum bulbosae of some stripes of Bromus tectorum, Eryngium campestre, Thymus pannonicus, Xeranthemum annum, Achillea setacea etc., species which are not consumed by animals. Table 3 Ass. Artemisio Poëtum bulbosae I. Pop 1970 No. of survey Altitude (m.s.m.) Exposition NV NE SE SE SV Slope (degrees) Coverage of the vegetation (%) Surface (sq.m.) K

12 68 Didia Popa et al. 12 Number of species Caract. of ass. Artemisia austriaca V Poa bulbosa V Jurineo-Euphorbinenion Ajuga laxmannii + + II Eryngium campestre V Euphorbia glareosa II Galium humifusum + + II Jurinea arachnoidea + + II Festucion valesiacae Asperula cynanchica + I Astragalus onobrychis + + II Chondrilla juncea III Dichanthium ischaemum IV Festucetalia valesiacae Achillea setacea V Centaurea biebersteinii + + I Linum austriacum + + II Echium vulgare II Festuca valesiaca V Salvia nemorosa + + I Sanguisorba minor + I Sideritis montana + I Thymus pannonicus III Verbascum speciosum + I Veronica prostrata + I Festucetalia vaginatae Alyssum desertorum + + II Anthemis ruthenica III Bromus squarrosus + + II B. tectorum IV Cynanchum acutum + I Erysimum diffusum + + II Plantago scabra II Potentilla arenaria IV Scabiosa argentea II S. ochroleuca + I Tragus racemosus III Festuco Brometea Centaurea diffusa III Cynodon dactylon + + II Herniaria glabra + + II

13 13 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 69 Plantago lanceolata II Poa angustifolia + + II P. bulbosa V Potentilla argentea II Xeranthemum annuum IV Artemisitea et Stellarietea mediae s.l. Alyssum alyssoides + I Berteroa incana III Carduus nutans II Centaurea solstitialis + I Cichorium intybus III Consolida regalis + I Conyza canadensis + I Descurainia sophia II Diplotaxis muralis + I Erodium cicutarium III Lappula squarrosa + I Lepidium campestre + I Marrubium peregrinum + I Medicago lupulina + + II Onopordon acanthium + I Senecio vernalis + + II Sisymbrium loeselii + + II Variae syntaxa Arenaria serpyllifolia II Filago arvensis + + II Trifolium arvense + + II Veronica arvensis + + II Place and date of the surveys: 1. Suceveni, ; 2. Jorăşti, ; 3 4. Vlădeşti, ; 5. Roşcani, ; 6. Folteşti, ; 7. Crăieşti, The bioforms spectrum (Fig. 7) is dominated by terophytes (42.5%) and hemicryptophytes (33.3%). The phytogeographic elements spectrum (Fig. 8) is defined by a high percentage of Eurasiatic elements (57.4%) and also a significant percentage of Pontic elements (20.3%). The ecological indices spectrum (Fig. 9) is similar to associations above, dominated by xeromesophile and xerophile species (92.5%), mesophile and moderate-termophile (81.4%), low acid-neutrophilic (55.5%) and euriionic (25.9%). From the economical point of view association is insignificant, since Poa bulbosa has low forager importance and Artemisia austriaca is considered to have a bad influence on the quality of milk.

14 70 Didia Popa et al. 14 Ch T H Ht Ht-H Fig. 7. The bioforms spectrum in the Artemisio austriacae Poëtum bulbosae ass. Euras Eur. Eur.centr Circ. Cosm. Adv. Med(submed) Pont. Fig. 8. The phytogeographic elements spectrum in the Artemisio austriacae Poëtum bulbosae ass. 100% 80% 60% 40% 20% 0% U T R Error! 6,00 5,50 5,00 4,50 4,00 Fig. 9. The ecological indices spectrum of the Artemisio austriacae Poëtum bulbosae ass. (U = humidity, T = temperature, R = soil reaction). 3,50 3,00 2,50 2,00 1,50 1,00 Ass. Cynodonti-Poëtum angustifoliae (Rapaics 1927) Soó 1957 Chorology. The association is not very spread and was identified around localities Rogojeni and Costache Negri. Stationary conditions. Phytocoenosis in this associations lives on planes and fertile meadow and sometimes salted, with variable humidity, sometimes flooded or drained during summer. The floristic and phytocoenological composition (Table 4). Phytocoenosis consisting of Cynodon dactylon and Poa angustifolia, have a heterogeneous floristic composition due the variable stationary condition. Therefore, along with xerophile xeromesophile species from class Festuco Brometea, most frequent are Galium humifusum, Eryngium campestre, Potentilla argentea, Centaurea diffusa etc., vegetates mesophile species from the class Molinio Arrhenatheretea, and also plants form the claselor Artemisietea and Stellarietea mediae. The main two species, Cynodon dactylon and mainly Poa angustifolia, covers around 40 60%, but, in some cases, species like Artemisia austriaca,

15 15 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 71 Achillea setacea, Trifolium campestre, Elymus repens and Lolium perenne are significant, covering from 5% to 20%. Table 4 Ass. Cynodonti-Poëtum angustifoliae (Rapaics 1927) Soó 1957 No. of survey Altitude (m.s.m.) Exposition Slope (degrees) K Coverage of the vegetation (%) Surface (sq.m.) Number of species Caract. of ass. Cynodon dactylon V Jurineo-Euphorbinenion Dianthus leptopetalus + I Eryngium campestre V Erysimum odoratum + + II Euphorbia glareosa + + II Galium humifusum IV Jurinea arachnoidea + I Festucion valesiacae Allium rotundum + I Artemisia austriaca V Chondrilla juncea + + II Dichanthium ischaemum + I Erysimum hispidus + + II Medicago falcata + + II M. minima + I Festucetalia valesiacae Achillea setacea V Centaurea biebersteinii III Echium vulgare + I Euphorbia cyparisias III Festuca valesiaca III Hypericum perforatum + I Lactuca viminea + I Linum austriacum + I Ononis spinosa + I Salvia nemorosa III Trifolium campestre 1 + II Verbascum speciosum + + II

16 72 Didia Popa et al. 16 Festuco Brometea Acinos arvensis + I Asperula tenella + I Centaurea diffusa V Crepis foetida ssp. rhoeadifolia IV Daucus carota + + II Hieracium pilosella + I Plantago lanceolata III Poa angustifolia V Potentilla argentea V Molinio Arrhenatheretea s.l. Agrostis stolonifera IV Alopecurus pratensis + + II Bromus commutatus + I Cichorium intybus IV Elymus repens V Erodium cicutarium + + II Lolium perenne V Lotus corniculatus + I Medicago lupulina IV Plantago major + I Potentilla reptans + + II Prunella vulgaris + I Rorippa austriaca + I Taraxacum officinale + + II Tragopogon pratensis ssp. orientalis + I Trifolium fragiferum + + II T. pratense + + II T. repens IV Artemisietea et Stellarietea mediae s.l. Anagallis arvensis + I Artemisia absinthium + I Berteroa incana III Cardaria draba + I Carduus acanthoides III C. nutans + II Cirsium arvense + I Convolvulus arvensis IV Erigeron annuus III Lathyrus tuberosus + I Lepidium campestre + I Vicia tetrasperma + I Xanthium spinosum + I

17 17 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 73 X. strumarium + + II Variae syntaxa Arenaria serpyllifolia + + II Centaurium erythraea + I Coronilla varia + I Juncus gerardi + I Lotus glaber + I Place and date of the surveys: 1 3. Costache Negri ; 4 5. Rogojeni, We also have to mention to rare and in danger species, Dianthus leptopetalus and Lactuca viminea, threatened by intensive depasturage. The bioforms spectrum (Fig. 10). The floristic composition is dominated by hemicryptophytes (49.2%), followed by terophytes and hemiterophytes (38%), but also important are geophytes (11.1%). The phytogeographic elements spectrum (Fig. 11) is dominated by Eurasiatic elements (52.3%), a significant percentage of Pontic, cosmopolite, circumpolar and European, central-european elements (6 15%). H T Ht G Euras Pont Cosm Circ Eur Eur Centr Medit Fig. 10. The bioforms spectrum in the Cynodonti Poëtum angustifoliae ass. Fig. 11. The phytogeograhic elements spectrum in the Cynodonti Poëtum angustifoliae ass. The ecological indices spectrum (Fig. 12) proof the majority of the species are xeromesophile and xerophile (58.7%), but also important are mesophile species (23.8%) and even mesohygrophilic (6.3%). Also, the majority consists of moderate-termophile (34.9%) and low slab acido-neutrophile and neutrophile (50.6%). Economical significance. Association has an average forager productivity since main species are low quality forage and also due the intrusion of some toxic species (Eryngium campestre, Artemisia austriaca, Euphorbia glareosa, Carduus acanthoides, Carduus nutans, Cirsium arvense, Xanthium spinosum, Xanthium strumarium etc.).

18 74 Didia Popa et al. 18 R T U 0% 20% 40% 60% 80% 100% c Fig. 12. The ecological indices spectrum of the Cynodonti Poëtum angustifoliae ass. (U = humidity, T = temperature, R = soil reaction). Ass. Bromo squarrosi Xeranthemetum annui Coroi 2001 Chorology. Is a relatively new association appearing in degraded pastures. In the investigated area, was identified only around the locality Brăneşti. Stationary conditions. Asociations Bromus squarrosus and Xeranthemum annuum are spread in small islands, vegetating on dry terrains (and sometimes sandy banks), on planes or moderate inclination hills. The floristic and phytocoenological composition (Table 5). Phytocoenosis formed by Xeranthemum annum represents a degraded stage of the association Taraxaco serotinae Festucetum valesiacae having a poor floristic composition (62 species). Therefore, floristic composition is dominated by species characteristic class Festuco-Brometea (60%), where the most frequent are: Salvia austriaca, Euphorbia glareosa, Artemisia austriaca, Salvia nemorosa, Galium verum, Poa angustifolia etc. Along with species above vegetates an important number (27%) of species characteristic to the classes Artemisietea and Stellarietea mediae, accentuating decay process of pastures. Phytocoenosis are covering around 90% of the land and are dominated by Xeranthemum annuum and Bromus squarrosus. In some phytocoenosis the species Euphorbia glareosa, Dichantium ischaemum, Artemisia austriaca and Echium vulgare, are covering around 5 10%. Table 5 Ass. Bromo squarrosi Xeranthemetum annui Coroi 2001 No. of survey K Altitude (m.s.m.) Exposition E E SE E SE Slope (degrees)

19 19 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 75 Coverage of the vegetation (%) Surface (sq.m.) Number of species Caract. of ass. Bromus squarrosus V Jurineo-Euphorbinenion Ajuga laxmannii + I Eryngium campestre + + II Euphorbia glareosa IV Galium humifusum III Salvia austriaca V Stachys germanica + + II Festucion valesiacae Artemisia austriaca V Asperula cynanchica + I Dichanthium ischaemum III Koeleria macrantha + + II Medicago falcata III Sanguisorba minor + + II Festucetalia valesiacae Achillea setacea + + II Centaurea biebersteinii III Echium vulgare III Euphorbia cyparissias + I Festuca valesiaca III Galium verum IV Hieracium bauhinii + I Linum austriacum III Melica ciliata + I Salvia nemorosa V Trifolium campestre + + II Verbascum speciosum + I Festucetalia vaginatae Alyssum desertorum + I Anthemis ruthenica III Bromus tectorum + + II Erysimum diffusum III Potentilla arenaria + I Scabiosa ochroleuca + + II Festuco - Brometea Crepis foetida ssp. rhoeadifolia IV Daucus carota + + II Plantago lanceolata + I

20 76 Didia Popa et al. 20 Poa angustifolia V Potentilla argentea + + II Xeranthemum annum V Molinio-Arrhenatheretea s.l. Bromus commutatus III Lotus corniculatus + I Medicago lupulina III Polygonum aviculare + I Serratula tinctoria + + II Taraxacum officinale V Tragopogon pratensis ssp. orientalis + I Trifolium repens + + II Artemisietea et Stellarietea mediae s.l. Anthriscus sylvestris + + II Artemisia absinthium + + II Berteroa incana + + II Cichorium intybus + I Cirsium vulgare + I Convolvulus arvensis V Erigeron annuus III Erodium cicutarium + I Filago arvensis + + II Marrubium vulgare V Matricaria perforata + + II Melilotus officinalis + + II Nigella arvensis + I Reseda lutea + I Trifolium arvense + I Xanthium spinosum + + II X. strumarium + + II Place and date of the surveys: 1 3. Brăneşti, ; 4 5. Brăneşti, The bioforms spectrum (Fig. 13) is dominated by terophytes and hemiterophytes (53.7%) followed hemicryptophytes 41.4%. The phytogeographic elements spectrum (Fig. 14) proof the dominance of Eurasiatic elements (65.8%), along with Pontic elements (17%). Also adventive elements were remarked (4.8%). The ecological indices spectrum (Fig. 15) reveal the clear dominance of xeromesophile and xerophile (76.9%), mesophile and termophile species (84.5%) and low acid-neutrophilic (53.8%). Economical significance. Pastures consisting of Xeranthemum annuum have a low economical importance, being improper for forage.

21 21 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 77 Ht T Ht G Ch Fig. 13. The bioforms spectrum in the Bromo squarrosi Xeranthemetum annui ass. Euras Pont Eur Centr Adv Cosm Fig. 14. The phytogeographic elements spectrum in the Bromo squarrosi Xeranthemetum annui ass. R T c U 0% 50% 100% 0 1 1,5 2 2,5 3 3,5 4 4,5 5 5,5 6 Fig. 15. The ecological indices spectrum of the Bromo squarrosi Xeranthemetum annui ass. (U = humidity, T = temperature, R = soil reaction). Ass. Brometum tectorum Bojko 1934 Chorology. Phytocoenosis formed by Bromus tectorum appeared during the degradation of pastures of Festuca valesiaca, identified around localities Suceveni, Zărneşti, Jorăşti, Slobozia Oancea, Rediu, Corod, Crăieşti, Rogojeni, Ghingheşti. Stationary conditions. Association Brometum tectorum prefer planar sandy banks, and rarely moderate inclination hills, usually exposed to south. The floristic and phytocoenological composition (Table 6). Cause the restrictive stationary conditions, floristic composition is reduced (56 species) with a remarkable kernel (more than 20%) species characteristically for the alliance Bromion tectorum and order Festucetalia vaginatae. Therefore, main specie Bromus tectorum is frequently accompanied by Bromus squarrosus, Plantago scabra, Allysum desertorum, Anthemis ruthenica, Centaurea diffusa, Cynodon dactylon etc.

22 78 Didia Popa et al. 22 Floristic composition of the associations is fragmented by numerous species (around 30%) characteristically to the order Festucetalia valesiacae and class Festuco-Brometea, from among we remark Artemisia austriaca, Eryngium campestre, Achillea setacea, Echium vulgare, Poa bulbosa, Plantago lanceolata etc. Association is invaded by numerous weeds caracteritically to classes Artemisietea şi Stellarietea mediae, where most frequent are: Cardaria draba, Convolvulus arvensis, Senecio vernalis, Onopordon acanthium, Sisymbrium loeselii etc. Table 6 Ass. Brometum tectorum Bojko 1934 No. of survey Altitude (m.s.m.) Exposition SV S SE SE SV SE SV V SE S Slope (degrees) K Coverage of the vegetation (%) Surface (sq.m.) Number of species Caract. of ass. Bromus tectorum V Bromion tectorum Bassia laniflora + + I Bromus squarrosus III Onobrychis arenaria II Plantago scabra III Festucion vaginatae Alyssum desertorum IV Anchusa ochroleuca II Anthemis ruthenica V Festucetalia vaginatae Centaurea diffusa IV Cynanchum acutum + + I Cynodon dactylon III Helichrysum arenarium + + I Festucion valesiacae Artemisia austriaca IV Chondrilla juncea II Eryngium campestre IV Koeleria macrantha III Erysimum diffusum II Stachys germanica II Festucetalia valesiacae Achillea setacea V

23 23 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 79 Echium vulgare IV Melica ciliata + + I Salvia nemorosa + + I Festuco Brometea Crepis foetida ssp. rhoeadifolia II Hieracium pilosella III Plantago lanceolata V Poa angustifolia II P. bulbosa IV Potentilla argentea III Artemisietea et Stellarietea mediae s.l. Anagallis arvensis + + I Berteroa incana + + I Capsella bursa-pastoris II Cardaria draba III Carduus acanthoides + + I Chenopodium album + I Cirsium vulgare II Convolvulus arvensis IV Geranium pusillum II Erodium cicutarium II Filago arvense II Hordeum murinum III Lappula squarrosa III Marrubium peregrinum III Melilotus officinalis + I Nigella arvensis II Onopordon acanthium III Reseda lutea II Scleranthus annuus + I Senecio vernalis V Sisymbrium loeselii III Variae syntaxa Bromus commutatum + + I Medicago lupulina II Rumex crispus + I Thlaspi perfoliatum II Trifolium repens + I Verbascum phlomoides II Veronica arvensis + + I Place and date of the surveys: 1. Suceveni ; 2. Zărneşti ; 3. Jorăşti, ; 4. Slobozia Oancea ; 5. Rediu, ; 6. Corod ; 7. Crăieşti, ; 8. Crăeşti, ; 9. Rogojeni, ; 10. Ghingheşti,

24 80 Didia Popa et al. 24 The bioforms spectrum (Fig. 16) distinguish a high percentage of terophytes, hemiterophytes (61.3%) and hemicryptophytes. The phytogeographic elements spectrum (Fig. 17) is dominated by Eurasiatic elements (63.6%), but Pontic and European elements are also important. Ch T G H Ht Ht-H Fig. 16. The bioforms spectrum in the Brometum tectorum ass. Euras Eur. Eur.centr Circ. Cosm. Medit Pont. Fig. 17. The phytogeographic elements spectrum in the Brometum tectorum ass. The ecological indices spectrum (Fig. 18) reveals the dominance of xeromesophile and xerophile (79.9%), mesotherme (49%) and low acidneutrophilic (41.8%). 100% 80% 60% 40% 20% 0% U T R Fig. 18. The ecological indices spectrum of the Brometum tectorum ass. (U = humidity, T = temperature, R = soil reaction). Economical significance of those pastures is unimportant since the main species Bromus tectorum is low quality forage. Even this is a degraded specie phytocoenosis form this associations have an important role in stabilisation of sandy terrains (Sârbu, 1984). CONCLUSIONS The base for pastures in the investigated area is represented by the association Taraxaco serotinae Festucetum valesiacae useful for depasturage.

25 25 The ass. in cl. Festuco-Brometea from the Covurlui Plateau 81 Due the intensive depasturage, the association has a low forager value, mostly degraded and replaced with phytocoenosis form the association Taraxaco serotinae Botriochloetum ischaemi, also having low foragere value. The other species resulting from the degradation of pastures of Festuca valesiaca, namely Artemisio austriacae Poëtum bulbosae, Bromo squarrosi Xeranthemetum annui and Brometum tectorum have a poor floristic composition and most of them are not suitable for depasturage. Only the association Cynodonti Poëtum angustifoliae has an average furagere value, but also was found limited areas. REFERENCES 1. CĂZĂCEANU I., TURENSCHI E., Lucr. Şt. Inst. Agron. Ion Ionescu de la Brad Iaşi, 1959, CHIFU T., Anuar. Compl. Muz. Bucov., 2006, 17 19, CHIFU T., MÂNZU C., ZAMFIRESCU OANA, Flora & vegetaţia Moldovei (Romania). II. Vegetaţia, Edit. Univ. Al. I. Cuza Iaşi, CIOCÂRLAN V., Flora ilustrată a României. Pteridophyta et Spermatophyta, Edit. Ceres, Bucureşti, MITITELU D., SÂRBU I., PĂTRAŞC ADRIANA, GOCIU ZOE, OPREA A., Bul. Grăd. Bot. Iaşi, 1993, 4, OLTEAN M., NEGREAN G., POPESCU A., ROMAN N., DIHORU G., SANDA V., MIHĂILESCU SIMONA, St., Sint., Docum. de Ecol., 1994, 1, SANDA V., BIŢĂ-NICOLAE CLAUDIA, BARABAŞ N., Flora cormofitelor spontane şi cultivate din România, Edit. Ion Borcea Bacău, SANDA V., VICOL IOANA, ŞTEFĂNUŢ S., Biodiversitatea cenostructurală a învelişului vegetal din România, Edit. ARS DOCENDI, Bucureşti, SÂRBU I., Volum Festiv Muz. Inst. Naţ. Iaşi, 1984, SÂRBU I., OPREA A., TĂNASE C., Bul. Grăd. Bot. Iaşi, 1995, 5, SÂRBU I., OPREA A., TĂNASE C., Bul. Grăd. Bot. Iaşi, 1997, 6, 1, SÂRBU I., OPREA A., TĂNASE C., Bul. Grăd. Bot. Iaşi, 1997, 6, 2: Received January 11, Dunărea de Jos University of Galaţi 2 Alexandru Ioan Cuza University, Faculty of Biology Corresponding author: chifutoader@yahoo.com

26 82 Didia Popa et al. 26